This project is to continue research on the use of anticancer antibodies labeled with radionuclides for cancer detection and localization by external scintigraphy. New antibodies developed against colorectal, lung, liver and other tumors will be evaluated experimentally and clinically as Tc-99m imaging agents, using a new Tc-99m direct labeling method. Radioimmunotherapy with murine Mabs, human Mabs, humanized MAbs and single- chain antibodies labeled with I-131, Y-90, or Re-186/188 will be pursued in animal models and subsequently in clinical trials. Promising lymphoma radioimmunotherapy with a new B-cell lymphoma MAb labeled with I-131 will continue. Other projects to be pursued include the use of a new lung metastatic model of human colonic cancer in nude mice to assess the effects of adjuvant radioimmunotherapy on survival; relationships of tumor and vascular physiology to antibody and accretion; reduction of myelotoxicity with cytokines.